1. Typical of the grassland¹ dwellers² of the continent is the American antelope³, or pronghorn.

2. Of the millions who saw Haley’s comet in 1986, how many people will live long enough to see it return in the twenty-first century.

3. Anthropologists have discovered that fear, happiness, sadness, and surprise are universally reflected in facial expressions.

4. Because of its irritating effect on humans, the use of phenol as a general antiseptic has been largely discontinued.

5. Insgroupsto remain in existence, a profit-making organization must, in the long run, produce something consumers consider useful or desirable.

6. The greater the population there is in a locality, the greater the need there is for water, transportation, and disposal of refuse.

7. It is more difficult to write simply, directly, and effectively than to employ flowery but vague expressions that only obscure one’s meaning.

8. With modern offices becoming more mechanized, designers are attempting to personalize them with warmer, less severe interiors.

9. The difference between libel and slander⁴ is that libel is printed while slander is spoken.

10. The knee is the jointswheresthe thigh⁵ bone meets the large bone of the lower leg.

11. Acids are chemical compounds that, in water solution, have a sharp taste, a corrosive⁶ action on metals, and the ability to turn certain blue vegetable dyes red.

12. Billie Holiday’s reputation as a great jazz-blues singer rests on her ability to give emotional depth to her songs.

13. Essentially⁷, a theory is an abstract, symbolic⁸ representation of what is conceived to be reality.

14. Long before children are able to speak or understand a language, they communicate through facial expressions and by making noises.

15. Thanks to modern irrigation, crops now grow abundantly in areasswheresonce nothing but cacti⁹ and sagebrush could live.

16. The development of mechanical timepieces spurred the search for more accurate sundials with which to regulate them.

17. Anthropology¹⁰ is a science in that anthropologists use a rigorous set of methods and techniques to document observations that can be checked by others.

18. Fungi¹¹ are important in the process of decay, which returns ingredients to the soil, enhances soil fertility, and decomposes¹² animal debris¹³.

19. When it is struck, a tuning¹⁴ fork produces an almost pure tone, retaining its pitch over a long period of time.

20. Although pecans are most plentiful in the southeastern part of the United States, they are found as far north as Ohio and Illinois

1.美洲羚羊，或称叉角羚，是该大陆典型的草原动物。

2. 1986年看见哈雷慧星的千百万人当中，有多少人能够长寿到足以目睹它在二十一世纪的回归呢？

3.人类学家们已经发现，恐惧，快乐，悲伤和惊奇都会行之于色，这在全人类是共通的。

4.由于苯酚对人体带有刺激性作用，它基本上已不再被当作常用的防腐剂了。

5.任何盈利组织若要生存，最终都必须生产出消费者可用或需要的产品。

6.一个地方的人口越多，其对水，交通和垃圾处理的需求就会越大。

7.简明，直接，有力的写作难于花哨，含混而意义模糊的表达。

8.随着现代办公室的日益自动化，设计师们正试图利用较为温暖而不太严肃的内部装饰来使其具有亲切感。

9.诽谤和流言的区别在于前者是书面的，而后者是口头的。

10.膝盖是大腿骨和小腿胫的连接处。

11.酸是一种化合物，它在溶于水时具有强烈的气味和对金属的腐蚀性，并且能够使某些蓝色植物染料变红。

12. Billie Holiday’s作为一个爵士布鲁斯乐杰出歌手的名声建立在能够赋予歌曲感情深度的能力。

13.理论在本质上是对认识了的现实的一种抽象和符号化的表达。

14.儿童在能说或能听懂语言之前，很久就会通过面部表情和靠发出噪声来与人交流了。

15.受当代灌溉(技术设施)之赐，农作物在原来只有仙人掌和荞属科植物才能生存的地方旺盛的生长。

16.机械计时器的发展促使人们寻求更精确的日晷，以便校准机械计时器。

17.人类学是一门科学，因为人类学家采用一整套强有力的方法和技术来记录观测结果，而这样记录下来的观测结果是供他人核查的。

18.真菌在腐化过程中十分重要，而腐化过程将化学物质回馈于土壤，提高其肥力，并分解动物粪便。

19.音叉被敲击时，产生几乎纯质的音调，其音量经久不衰。

20.虽然美洲山河桃树最集中于美国的东南部但是在北至俄亥俄州及伊利诺州也能看见它们。